AUSTIN — Manny Diaz's old employer would tell him this is simply the way things work. Just because you're glorified one day doesn't mean you can't be demonized the next, and just because an issue is full of complicated subtleties doesn't mean people can't scream about it.

Some days, Diaz might wish he were back at ESPN so he could do some screaming himself.

Instead, the former TV production assistant is running the Texas defense, and it's an unmitigated ratings disaster. In terms of yards allowed per game, the Longhorns rank 107th in the country and dead last in UT program history. One year after leading the Big 12, Diaz's group has been worse than Rice, New Mexico State and every slow-footed, backpedaling unit assembled by John Mackovic.

That's the kind of development that not only riles up a talking head, but also a fan base. Two months ago, UT supporters worried about losing Diaz to Arkansas. Now, they'd just as soon see him jump on the back of Bobby Petrino's motorcycle and never come back.

Still, Diaz smiles. Yes, opponents keep eating up yardage in gluttonous chunks, and yes, his defense has been about as effective at preventing repeated helpings as the sneeze guards at Golden Corral. But asked Monday if he's doubting his coaching ability or his schemes, he said his eternal positivity hasn't been shaken.

“How could it?” he said.

To hear Diaz and his boss, Mack Brown, tell it, nothing about the UT defense is broken. Both acknowledge there are details that need to be fixed, and that the tackling — atrocious at times this season — needs to improve. But every week, Diaz insists the game tape is full of things his players are doing right and that they're close to putting it all together.

And even though Diaz knows some would like to hear him talk about scrapping his playbook or overhauling his depth chart, he said he prefers not to do anything so drastic.

“Persistence is so uncool,” Diaz said. “It would be so easy to walk in there and erase the board and say we're going to the Pittsburgh Steelers defense. ... It's so easy to press the reset button on the video game. It's hard to stay and fight.”

Fighting hasn't been the Longhorns' only defensive problem, though. While giving up 197 points and 2,320 yards in the last four weeks, players have not only missed tackles but consistently blown assignments and been out of position. Safety Kenny Vaccaro said sometimes teammates even have struggled to line up properly.

But he said the issue isn't Diaz's system.

“It worked last year,” Vaccaro said. “Why wouldn't it work now?”

The answer to that is nuanced. For one thing, the rest of the Big 12 has a year of tape to work with. But more significantly, the Longhorns lack experience at crucial spots on the field.

Diaz's best defenses, the ones he had in 2010 at Mississippi State and last year at UT, were loaded with star veterans. Since Jordan Hicks went down during the third game this year, UT has no seasoned linebackers and is rotating three unpolished safeties alongside Vaccaro. The middle of the field is a mess. It could be that Diaz simply isn't as good at working with raw players as Will Muschamp was. And even though Brown won't criticize him publicly, it could be that Diaz is hearing about it behind closed doors.

“Everybody is held accountable in our building,” Brown said.

With that in mind, Diaz might have another reason to remember his old job.